Scientist-led K-12 outreach offers many benefits to scientists, teachers, and students; however, many of these programs are top down rather than collaborative. Our team facilitated a museum-based scientist-teacher partnership to co-design a lesson on shark biology for middle school students. Following the implementation of the lesson, we conducted interviews with the scientist and teacher participants. The participants described several benefits for the students including contextualizing science in the real world, providing exposure to new careers, and humanizing scientists. Teacher benefits included increased content knowledge and feeling reenergized to teach their subject. The scientist gained knowledge about science standards and classroom pedagogy. The challenges to the partnership included time constraints and restrictions enforced by the school districts. Using the findings from our study, we describe how other organizations can facilitate similar scientist-teacher partnerships to help improve science literacy and career aspirations. Scientist-teacher partnerships are highly effective for improving scientists' communication skills, increasing teachers' content knowledge, and contextualizing science for students.